A Hidden Cause of Chronic Pain: Why Your Brain Sometimes Won’t Let Go of Pain

For years, painful knee arthritis hobbled you. Then you had a knee replacement. Why are you still in pain?

Blame it on your brain. “Your brain gets used to prolonged exposure to pain signals and adjusts to them,” explains pain management specialist Robert Bolash, MD.

It’s like adjusting to the weather when you move from Ohio to Florida, he says. When you first arrive, you’re hit by the heat and humidity. But over a long period of time, your body acclimates, and you can enjoy the weather.

In contrast, when your brain gets used to pain signals — a problem called central sensitization — you gain little benefit from it.

Two types of pain

Peripheral pain is the sharp or aching pain you feel locally — say, when bone rubs against bone in your knee.

Centralized pain is a more complicated type of pain facilitated by the brain and spinal cord.

“We’re realizing more and more that addressing only peripheral pain is not enough for patients who also have centralized pain,” says Dr. Bolash.

He compares peripheral pain to a rock concert. It’s easy to hear the wailing guitars and pounding drums during the event.

“But when the band goes home, chronic pain patients with central sensitization still hear the music,” he notes.

Problems linked to centralized pain

Traditionally, doctors thought centralized pain only occurred with nerve injuries such as spinal cord injury or stroke.

“But the more we learn about centralized pain, the more we see it with other conditions,” says Dr. Bolash. These include:

• Arthritis.
• Fibromyalgia.
• Irritable bowel syndrome.
• Chronic low back pain.
• Neck pain or whiplash.
• Chronic headaches.
• Chronic pelvic pain due to endometriosis.
• Persistent pain after surgery.
• Chronic fatigue syndrome.

Each type of pain is treated differently

Classically, doctors treat peripheral pain with medications to decrease inflammation; injections; or surgery to correct the underlying problem.

For example, anti-inflammatory drugs (NSAIDs), such as Motrin®, Advil® or Aleve®, would be used to treat inflammatory pain from osteoarthritis.

“However, these medications don’t do a great job in the central nervous system, so we need to explore other agents,” explains Dr. Bolash.

For centralized pain, doctors can use medications that act on the brain or spinal cord, such as:

• Amitriptyline.
• Pregabalin.
• Duloxetine.
• Venlafaxine.

Seeing a psychologist can also be critical in addressing central sensitization. A pain psychologist would be ideal, but any psychologist who offers cognitive behavioral therapy (CBT) can help.

Learning stress management techniques and addressing anxiety have also proven to be effective treatments.

“The solution doesn’t have to be pharmacological for everyone,” he notes. 

Feeling better = doing more

Pain specialists historically asked people to score their pain on a scale from 0 to 10 to see how well treatment was working. “But we’ve found that the pain score is not particularly useful,” says Dr. Bolash.

For example, two people can have a pain score of 8, but one may spend all day on the couch, while the other goes out shopping and interacts with their family.

“We like to measure success based on activity, rather than pain intensity,” he says. So instead of treating a number, pain specialists look for functional improvement.

They often find that, when centralized pain is treated, people can do activities they previously curtailed due to pain.

“Increased socialization and improved interpersonal relationships are two things that mark success with pain treatment,” notes Dr. Bolash.

So if you’ve lived for years with spine pain, knee pain, headaches, arthritic pain or persistent pain after a successful surgery, see a pain specialist.

You may need help for centralized pain. “It’s often the missing piece,” says Dr. Bolash.